1. Field of the Invention
The present invention relates to a processing method for a semiconductor device wafer, and more particularly to a technique of facilitating the handling of a semiconductor device wafer reduced in thickness.
2. Description of the Related Art
In processing a wafer having a plurality of devices on the front side, such as a semiconductor device wafer and an optical device wafer, the back side of the wafer is ground to reduce the thickness of the wafer to 50 μm or less, for example.
When the thickness of the wafer is reduced to 50 μm or less, the handling of the wafer becomes more greatly difficult as compared with the case that the thickness is larger. For example, there arises a problem such that chipping occurs on the outer circumference of the wafer or the rigidity of the wafer is remarkably reduced.
As a technique to cope with this problem, it is known that the back side of the wafer is ground in the condition where the front side (device formed side) of the wafer is attached through an adhesive or the like to the front side of a carrier wafer (which is also referred to as a support wafer or a support plate) formed of glass or silicon.